Electric fuse



Patented Aug. 14, 1923.

1,464,903 zearzsnrr .orri csj;

"FREDERICK A. EELDKAMP, or NEWARK,.NEXVYJERSEWY. Q

I CEiL-IEKIi'lRIG EUSE.

,a ncationmea :August 26, 1921. 1 Serial No. 495,648.

To allwhom fi m ng concern :Beitzknownthat 1,.Ennonnro1r A. Few- .KAMnaa citizen or" tthe United :States, residingeat. Newarlgdn theecounty oi Essex'and State of New Jersey, haveinvented certain new and -usefulImprovements in -Electric Buses ;.'and l do hereby declare the tollow- .irrgfito. be a? full, 'C1B&I','i&lld exact description .of. the invention; sue-h; aswillnena-hle others skilled in ithefartitoiiwhich itnappertains to make andnse the samegreiterence beingrhad to thexaeoompanying idrawings, and to charraeters of reference i marked thereon, which f'ormea part: of this-specification.

iT-hlS invention relates, generally, to .-,in1- wprovementsu in fuse cartridges ;-iand. the in- .vention has re-tferenc rmore particularly, to a no vel oonstnuction of renewable :01 Ire fillable i fuse cartridge.

The invention has for its princ i-pal object t0;.provide a constnuctioneof:renewable or refillable tuse 'earitnidge adapted-1350; greatly simplify the (method 10f renewing blown fuses, whereby the operative manipulations required :are a reduced 2 :to a zim-ini-murn. iTo

. this end I; wprovideiria- "novel; form; otexternal :shell on-container for; holding one or more .dns'ert or. -:-refi-llfuse-z eartsidges of! i substantially-conventional form gthe external shellor container being; so constructed that theflactfof inserting anew insert: or refill fuse cartridge .into operative relation thereto, automatically eisipels the previously blown fuse: cartridge. A furtherobjeictof thednyentionf is to-, provide= a znovel construction. on permanent; external shell or containenkWhi-ch permits the usesof zxinserts 1-01 refills wma'de in conventional fuse; cartride: .forrn, but 'whichiiby wreasonoffitheir rinc osure within 'said shell or: containenmay be (made i of cheaper i matemials. and smaller-sin. size, so'fthat {the loss consequently inn the blowing and destruction -of.theiisameizis greatly reduced. I

EA, still. further. objectrof the invention; is to; :provide; an :outer; shell; or container :of uegulation size to ffib'SilitIldiiICliSi-ZBS: of clips, whi'ehrcan be :used? oven-andaoven again; and iwhiehdsnot subj ect'ed-to the destructive and f deteriorating tefiects' of !the electric are consequent 1: 'uponithe blowin' .1 of; a: fuse, since the rsaid: tare is 'produceti only. Within, the .insertuon refill partridge. @Itthus follows thatzr'said 'rexternal' shell: iorcieontfiiin r is not SilliijiBCtltO highiheat ever time; alfuse blows, 111 s; zisi' the. easei iini' refilla" lereartiri-dges C0nstimated :toireceive? only. a: drop, out or *il'i fill shell :or container is enabled to render; long service, Without danger of disruption due 1 to; the-weakeningof its fibre wallasvl ile at the same tlllleit serves to confine and-reenforcejtheinsertor refill fuse cartridge or cartridges which it; is adapted to enclose.

. Other objects of this invention, not v at this time more particularly enumerated, will .he clearly understood. frornythe followingdetailed description on the same.

The invention is clearly illustrated the accompanying drawings in which 1- Figured is aside elevation of onefor n not .my novel. remoiza ble. fuse cart-ridge a Figure2is a longitudinal section of thelexternal shell or container, showingan insert or g-efill fuse cartri dge ,operat vely assoc ated Figure :5 isna longiltudii al section ,of..a

sert or refill fuse cartridges inlsuc'hl anianner nthat but one of. thejlatter is in service at ,atime.

. Figure 6 is also a longitudinal rsefction of a further .modifiedflformjof hQlClIiflI coir .tainen for, a .pluralityof insert or refill: ,fuse v cartridges. l l i Eigurefixis a part silde eleyationeand part longitudinal section i of another forin or sternal .shell] or ,container, embodying, how wer the, genera1, principles of th J- WQ Eigure 8 t is. av fragmentary sidejelevation .of the novel; external shell or icQnl ainer.

equipped. .with knife blajde :contacts; and

Figure?) is a longitlltlinal section and part elevation of theisam taken onj line 9 -9 ,in said Figure 8. 1 a S-imilar.,.characters of reference are em- ;ployl ed in. $111,015 ithe jhereinaboye described views, to indicate corresponding parts.

-. .Beferring nowi oi Figures lit tinehls v the ernbodimentnot my invention therein .i fuselink or element, and consequently the slightly modifiediorrn. of. externalshell or 1 container adapted .to, ,hold. a plurality of in shown; comprises an external shell o r container 10, .Which .is. ina, de,of -;fihre or other suitable non conducting ,or insulation rnaterial, andwhich.isrtuhnlar in iiorrn, hav ng at each end; suitably, secured thereto, rivets 11,;-or in any other g nyenient;manneume:

tallic end ferrules or contact caps 12, provided in their end walls with openings 13 of a diameter substantially conforming to the internal diameter of the shell or container 10. Arranged within each ferrule or contact cap 12 is a contact-sleeve 14 having at its inner end an annular enlargement 15 which engages the inner surface of the ferrule or cap 12, and which is secured to the latter by solder or other fastening means, whereby the same is both mechanically and electrically connected therewith. Each sleeve is provided with slits 16 extending longitudinally inward from the free end thereof, thus rendering the sleeve yieldingly expansible for purposes presently to be described. The reference character 17 indicates an insert or refill fuse cartridge of conventional construction and form, whereby the same is adapted to enclose a fuse element 18 extending between and electrically connected with the end contact caps 19 thereof. This insert or refill fuse cartridge 17 is made in proper dimensions, so that the same may be inserted endwise through an open end of the external shell or container to move telescopically thereinto, and so that, when in place, its respective contact caps 19 are engaged by the contact-sleeves 14, thereby electrically connecting the insert or refill fuse cartridge with'its fuse element 18 between the contact ferrules 12 of the shell or container 10. In order to assure a good electrical contact between the contact sleeves 14 and the contact caps 19 of the insert or refill fuse cartridge, the former are normally made slightly smaller in diameter than the diameter of said contact caps 19, and then provided with the slits 16 so that they will expand as the contact caps 19 enter the same, and will thereupon huggingly embrace the contact caps. The said external shell or container lOwith its end ferrules 12, is designed to possess the outside dimensions of a standard fuse-cartridge of any given'size and capacity to which it is to correspond, and consequently will fit corresponding clips for holding the same in circuit. The insert or refill cartridge 17 may be made of lighter and smaller sized and cheaper material, but with a fuse element of proper capacity.

When the novel fuse cartridge, consisting of the combined external shell or container 10 and insert of refill fuse cartridge 17, is in service, the current passes through one ferrule 12, contact sleeve 14, and end cap 19 into and through the fuse element 18, and thence through the opposite end cap 19, con tact sleeve 14 and out through the opposite ferrule 12.

WVhen the fuse element 18 blows, the external container or shell 10 is removed from the clips, and a new insert or refill fuse cartridge is taken and inserted into one end of the container or shell 10 to pass thereinto for proper enclosure therein. This operation forces the blown fuse cartridge out of the opposite end of the container or shell, so that it will be apparent that the one operation required to insert a new insert or refill fuse cartridge, automatically operates to expel the old or blown fuse cartridge from the external container or shell, thus greatly simplifying the method and manipulation required to renew the device for further service, and eliminating all necessity for takeapart operations generally required when using the heretofore known type of refillable fuse cartridges.

Referring now to Figure 7, I have shown therein a type of my novel renewable fuse cartridge, which involves a slight modification of the construction of the external container orshell. In this construction I eliminate the contact-sleeves 14, and in place thereof I strike out of the walls of the ferrules 12 inwardly depressed fingers or contact arms 20, which electrically engage and mechanically embrace the end caps 19 of the insert or refill cartridge 17, when the latter is operatively associated with the external container or shell. This construction is very cheap, and for certain classes of fuses very satisfactory.

Referring now to Figure 5, I have shown a modified form of removable fuse cartridge. which embodies the general principles of this invention, but which involves some additional features, whereby the external container or shell is adapted to hold a reserve insert or refill fuse cartridge in addition to the insert orrefill fuse cartridge which is active or in service. In this construction I provide a tubular external shell or container 21 made of a suitable insulating material, and provided at its respective ends with metallic end ferrules or contact caps 22, the latter being provided with the openings or passages 23 in their end walls. Arranged within the receiving end of said external shell or container 21 is a contact sleeve 24 which snugly fits the shell or container 21 and which is secured in place by rivets 25 or other suitable means, whereby the same. together with the adjacent end ferrule or contact cap 22, are fastened to the shell or container 21, and the sleeve 24 is at the same time electrically connected with said adja cent end ferrule or contact cap 22. Said contact sleeve 24 is provided at its outer end with an inwardly off-set annular gripping portion 26 having one or more longitudinal slits 27 to render the same expansible, and in like manner, said contact sleeve 24 is provided at its inner end with a similar inwardly off-set annular gripping portion 28, which is also provided with one or more 1011- gitudinal slits 29 to render the same expansible. Said contact sleeve 24 is of a length adapted to position said inner gripping pories-28 lie l -e-b y dit heater e the e t rn z h sereee iienim A ran ed-a ithin h repiwsit e '.flheh rg ieefl .e a ti eslim ye rl r a -utilit effine r 6 efil us C t dge 1 1 th gem lu a -in h z r' fi th s m i an e aed-t r i We eee' ,er efi es e dee 34 and 35, which are arranged nd to end so .that the contact cap 34" of ,theicartridge -34 is mhme b besr ee maipn :28 tith contact sleeve, 24, ,and the opposite contact an 23. fimh eee the e est mat tion 32 of the contacts sleeue ,.fwhile-the outer contact lcap -35" of the cartridge 35 is engaged by h gripp ng I po i n '26, of th contact v,sleeve 2 4, ,and'isthus held [against rearward: displacement,fromftheshell; or coritainer 21'. ,VVithithe cartridges and thus arranged, the forrner occupies an a ctive or inservlce(relat onto the shellg'or. conta ner 21,,while the'lat ter pccupies an .inactiveor short circuit "relation thereto." The electric Current is passedfrom one end ,ferrule or since apl into h eon'tact ee e 124. thence ,passing ,into tl1econtactcap 34 through the fuse of, the cartridge 34, :to ;the opposite Contact cap 34", and thence through the contact sleeve 30 to ,the" .,o.pposit e end e le 9 met t ap 2202 h -,$hQ .O Z-CQI1L- t'ainer 21. It will thuabe appareutthatthe cartridge 35 is short circuited by the contact sleeve 24 hand remains inactive, while the cartridge 34 carries the current load. v then the cartridge 34 blows and ;it.is esired to replace the same, a new. insert jlor nefill cartridge is thrust against the outward end of the cartridge 35, causing the latter to move longitudinally forward to an in service position while the new cartridge enters into reserve position within the shell or container 21 formerly occupied by said cartridge 35.

This shifting of the cartridge 35 not only carries the same to an in service 1 position, but also serves to eject the blown cartridge 34 from the shell or container 21. The cartridge 35 now has its contact cap 35 engaged ,with the inner end of the contact sleeve 24, while its contact 35 is engaged with the contact sleeve 30 of the shell or container 21 thus bridging the current from the former to the latter. It will be evident that this construction of my novel refillable fuse cartridge oflers a very advantageous arrangehPe iQY- ew. A, W understoofdithat thereserve fuse may be: In

Inent whereby: a reserverefill fuse, of pr pper a I wean d: l s i lels be git dinally shifted as v.activel'jposition13y fit ad se ss i rth en wi a handymeanslin absnceofianother nsert l e M0 igure .6, I haveshown another ar .of tlie 15st above described WP- 93 Q 13 hair-i551 :-i fi ?l sa etie In-Qthis storm, I have Qan gexternal shell or container 3:6,having the end ferrules the l tte h n s e s el 3-Pwv eedvwitb the passages or openings-39. Extending into the receiving .end ofsaid shell or container 4 1s feont e -sl ve 40, a ng a its ou e end {an M 5 1? Pr j t a n a :flen'e 41 ,which, extends under and is soldered to or otherwise secured beneath the ,end ,wallo-f the adjacent ,end --f ?ru1e cr /contact. cap 37 thus rnechanically and electrically securing h e e tisleev te he la te "The ner .end of said contact sleeve A0 -,i s- ,p'rovided iwith longitudinal slits 42 IO render th sam xpa i le while the body cf th I sleeve toward its outer end is likewise rpmvided with .slits;43,-wl1ereby an insert or refill cartrid e will be embraced'and'gripped against displacement. Extending :'into .the dischargee'nd of ,said ,shell ,or :container 236 is a second contact sleeve 144,,a1s0 having atjits outer end gan Qutwardly projected [annular flange 45 whichjextends under and is soldered to or otherwise securedbeneath'lthe end-wall of the adjacentend ferruleioriicontact cap '37 thusmechanic ally :and electrically securing the said contact sleeve to the latte Th i ne end 'ofrSifli'd-contiwt sleeve 44 is likewise provided with slits' 46' :to render the same expansible. .TW-b insert or refill cartridges/florid 48 are employed, the orme W ll-Dy ng :en in s ice pos t o id n i h ,gfiP between h i n lend vo th esp e ire enteet sleeve 0 n 4 rvh h let e cup es w'res rre' andish mire ute "pes t e withi h "out r end 1? .Jhe e teet sle efl @h m hedb rmen peletion and the advantages of this form of my refillable fuse cartridge are the same as already heretofore described in connection with the form shown in Figure 5 of the drawings. e

Referring now to Figures 8, and 9 of the drawings, I have shown a means of applying knife-blade contacts to the external shell or container of my novel refillable fuse cartridge. The reference character 49 indicates the external shell or container provided with the end ferrules 50. Said end ferrules 50' tact 54 is secured to the end of said cap 52,

preferably by rivet portions 55 which extend through the end wall of the said cap and through a copper disc 56 arranged within the cap, and adapted to provide agood electrical contact With the end ferrule over which the cap is engaged. By thrusting the caps over the end ferrules and properly engaging their bayonet slotswith the studs 51 of said ferrules, the knife-blades ma be properly alined, and both electrical y and mechanically secured to the shell or container 49 so as to be capable of quick detachment when removing and renewing the insert or refill fuse cartridges from said external shell or container.

I am aware that some changes may be made in the general arrangements and combinations of the various devices and parts of my present invention, without departing from the scope thereof as set forth in the foregoing specification andas defined in the appended claims. Hence, I do not limit my present invention to the exact arrangements and combinations of the various devices and parts as described in said specification, nor do I confine myself to the exact details of the construction of the said parts as illustrated in the accompanying drawings.

1. A fuse cartridge, comprising a tubular casing of insulating material having external metallic ferrules at its respective ends, said ferrules being open at their outer ends. internal annular contact sleeves respectively in fixed electrical engagement with said respective ferrules, said sleeves having expansible gripping portions, and a refill cartridge fuse of conventional form longitudinally movable into and out of said shell from either end thereof, said expansible gripping portions being adapted to engage the respective contact caps of said refill cartridge fuse to electrically connect the latter-between said internal contact sleeves.

2. A fuse cartridge, comprising a tubular easing having external contacts at its extremities, aninternal contact element electrically connected with one external contact of said casing to extend inwardly beyond the center of said casing interior, a'second internal contact element electrically connected with the opposite external contact of said casing to extend inwardly but spaced longitudinally from the first memtioned contact element, and a plurality of refill cartridge fuses of conventional form, one of the latter normally occupying an 'in service position electrically engaged with and longitudinally from the first mentioned sleeve, means rendering the opposed ends of said sleeves expansible, and a plurality of refill cartridge fuses of conventional form movable endwise into and out of said casing, one of the latter normally occupying an in service position electrically engaged with and between the opposed ends of said sleeves. 1

4. A refillable fuse cartridge comprising a tubular external shell having open outer ends and external contact members and adapted to hold a series of refill cartridge fuses in alinement, and means upon said tube for maintaining one only, of said cartridge fuses in electrical contact with said external contact members.

In testimony, that I claim the invention set forth above I have hereunto set my hand this 23rd day of August, 1921.

FREDERICK A. .FELDKAMP. Witnesses:

GEORGE D. RICHARDS, EVA E. DESGH. 

